Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
  • C22B13/00—Obtaining lead
  • C22B13/04—Obtaining lead by wet processes
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
  • C01G21/00—Compounds of lead
  • C01G21/16—Halides
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
  • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
  • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
  • C22B3/42—Treatment or purification of solutions, e.g. obtained by leaching by ion-exchange extraction
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P10/00—Technologies related to metal processing
  • Y02P10/20—Recycling

Definitions

• the object of this invention is a process for the treatment of solutions of lead chloride containing as impurities at least one metal chosen from the group consisting of silver, copper and bismuth.
• one of the goals of the present invention is to provide a process of purification of lead chloride solutions which makes it possible to eliminate almost all the silver, copper and bismuth present in this solution, and notably to lower the ratios of silver/lead, copper/lead and bismuth/lead to a level below 10 ppm.
• Another goal of the present invention is to furnish a process of the type above which does not consume a great deal of energy.
• the sulfhydry group (SH) may be eg: in the form of the following functional group: ##STR1## The two last ones being preferred.
• the present invention gives particularly good results and is particularly well adapted to problems posed by lead chloride solutions whose composition is indicated in the following ranges, giving the usual range and the preferred range:
• the sulfhydryl (-SH) particularly thiol groups make possible by themselves the complete elimination of the silver and bismuth present in the solution, whereas the elimination of copper is subject to another parameter, which is the oxido reduction potential of the solution. If the elimination of copper must be total, the copper must, as completely as possible, be in the cuprous form. Furthermore, the -SH groups present the disadvantage of being sensitive to oxidation.
• the solutions resulting from oxidizing leaching of galenas are in particular liable to contain traces of Fe +++ ions and bivalent copper. These two compounds, particularly the Fe +++ ions, partially destroy the active group of the resin.
• step (a) it is appropriate before realizing the purification of step (a) to reduce the solution to bring the entirety of the copper to the cuprous form, the apparent oxide reduction potential being advantageously lower than or equal to 0, and preferably at -520 millivolts with regard to the saturated calomel electrode, this latter being in the same conditions as the solution.
• the reduction can be likewise effected by the electrolytic method.
• the temperature of the solution during step (a) is preferably located between 60° C. and the boiling temperature.
• the pressure chosen is preferably atmospheric pressure. However, in certain cases pressures above or below atmospheric pressure can be used without altering the performance of the process.
• the resins used in the course of step (a) can be, for example, resins sold under the commercial designation of IMACTI GT 73 by the Imacti Company and the resin sold under the commercial designation of LEWATIT OC 1014 by the Bayer Company. These two resins have as their active group the sulfhydryl group (-SH).
• the solutions obtained after step (a) from the process according to the present invention have a silver, copper and bismuth content below the analytical detection limit; i.e., respectively below 0.1, 0.2 and 0.1 milligrams per liter.
• the lead can be recovered according to techniques already known, for example, by precipitating its salt, reducing it to the metallic state chemically or case-hardening it.
• one of the great advantages of purification according to the present invention is that it permits the direct acquisition of lead of high quality by electrolysis of the solution.
• Such electrolysis leads to the precipitation of lead whose purity can easily reach 99.95%, containing at the most 15 ppm of copper, 10 ppm of silver and 20 ppm of bismuth, the electrolysis having a tendency to raise the ratios between the impurites and the lead.
• Resins saturated with silver, copper and/or bismuth can be reclaimed in the following manner:
• the active groups When the active groups are altered by oxidation, they can be reclaimed by means of a solution of sodium sulfide.
• the objective of the following nonrestrictive examples is to put specialists in a position to determine easily the operative conditions which are suitable for use in each particular case.
• a solution is prepared which only contains chlorides of the following composition: NaCl 250 g/l; Pb +2 30 g/l; Fe +2 20 g/l; Bi +3 50 mg/l; Ag + 10 mg/l; and Cu + 10 mg/l.
• This solution is brought to the temperature of 90° C. and continuously passed through two columns in series.
• the first column contains lead turnings and effects a first purification by cementation of copper, silver and bismuth. Upon leaving this column, the solution contains less than 0.1 mg/l of bismuth and silver, but still 1 mg/l of copper.
• the second column contains an ion exchange resin sold under the trademark of LEWATIT OC 1014 whereof active group is thiourea.
• active group is thiourea.
• the content of copper, silver and bismuth is below the analytical detection limit specified above, the mass ratio between these impurities and the lead being 7, 3 and 3 ppm, (10-6) respectively.
• An output of 10 B.V./hr is achieved for 50 hours without observing an escape of copper in the solution.
• the solution resulting from corrosion effected according to the technique described in French patent application No. 76-22.138, published under the number 2,359,211, is treated in an installation including a storage tank for the solution resulting from the corrosion and a cementation reactor.
• This cylindrical reactor is composed of two superposed parts separated by an inclined partition in the form of a funnel.
• the impure corrosion solution is admitted into the lower compartment where the lead electrolytic powder is kept in suspension, causing the cementation of noble metals.
• the roughly purified solution is drawn off by an overflow system, in the upper part, not agitated, without an important carrying away of the solid.
• the two compartments of the reactor have a volume perceptibly equal to 0.85 liters.
• the installation also includes a column temperature controlled at 90° C. furnished with ion exchange resin sold under the trademark IMACTI GT 73.
• the solution coming from the cementation reactor is introduced at the base of this column, after clarification.
• the operational parameters of the purification are:
• the solution purified by the preceding step is then treated in an electrolysis installation.
• This installation includes:
• the pure solution of PbCl 2 is pumped into the cathode compartment where it is rid of part of the lead which it contains before going through the diaphragm to penetrate the anode compartment. After oxidation of the ions of Fe ++ to Fe +++ , the anolyte is eliminated from the container. The lead formed is recovered, measured, then melted in the presence of soda at 400° C. The ingot obtained corresponds to the following chemical analysis:
• the quality of the product obtained is remarkable. Only a very small copper contamination is observed.
• the treated product is a mixed concentrate of PbS-ZnS-CuFeS 2 , obtained by total flotation of solid pyrites of Aljustrel (Portugal). This product undergoes the following successive operations:
• the eliminated impurities are distributed in the following manner:
• the lead collected after the electrolysis is washed, then melted at 400° C. in the presence of soda.
• the resulting ingot has the following chemical analysis:
• the resin is first saturated using a synthetic solution of copper chloride in sodium chloride, titrating about 5 g/l of copper.
• the resin thus saturated contains, according to experiments, from 60 to 80 g/l of copper per liter.
• the elution solution is collected by fraction from a bed volume which will be designated as B.V. (Bed Volume), and a determination of the copper concentration is conducted for each fraction. It is thus possible to determine the proportion of copper eluted, as a function of the amount of elution solution collected, and depending on the various hydrochloric acidities.
• the resin according to the invention may be shipped by alcaline metals cyanides too.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Manufacturing & Machinery (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Geochemistry & Mineralogy (AREA)
• Environmental & Geological Engineering (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Geology (AREA)
• Inorganic Chemistry (AREA)
• Manufacture And Refinement Of Metals (AREA)
• Electrolytic Production Of Metals (AREA)
• Inorganic Compounds Of Heavy Metals (AREA)
• Separation Of Suspended Particles By Flocculating Agents (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=9229056

Family Applications (1)

Country Status (19)

Cited By (4)

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Citations (4)

Family Cites Families (2)

• 1979
  • 1979-08-24 FR FR7921325A patent/FR2463639A1/fr active Granted
• 1980
  • 1980-08-12 IE IE1688/80A patent/IE50094B1/en unknown
  • 1980-08-12 US US06/177,434 patent/US4297183A/en not_active Expired - Lifetime
  • 1980-08-14 GR GR62681A patent/GR69806B/el unknown
  • 1980-08-19 ES ES494351A patent/ES8106241A1/es not_active Expired
  • 1980-08-19 AU AU61562/80A patent/AU538721B2/en not_active Ceased
  • 1980-08-20 FI FI802623A patent/FI66921C/fi not_active IP Right Cessation
  • 1980-08-21 PT PT71719A patent/PT71719B/pt unknown
  • 1980-08-21 JP JP11533680A patent/JPS5638437A/ja active Granted
  • 1980-08-21 ZA ZA00805160A patent/ZA805160B/xx unknown
  • 1980-08-21 MX MX183625A patent/MX153805A/es unknown
  • 1980-08-22 PL PL1980226367A patent/PL123202B1/pl unknown
  • 1980-08-22 NO NO802512A patent/NO154748C/no unknown
  • 1980-08-22 DK DK362080A patent/DK148284C/da active
  • 1980-08-22 BR BR8005329A patent/BR8005329A/pt unknown
  • 1980-08-22 CA CA000358820A patent/CA1156471A/en not_active Expired
  • 1980-08-25 AT AT80401212T patent/ATE1831T1/de not_active IP Right Cessation
  • 1980-08-25 DE DE8080401212T patent/DE3061108D1/de not_active Expired
  • 1980-08-25 EP EP80401212A patent/EP0024987B1/fr not_active Expired

Patent Citations (4)

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